1. Field of the Invention
The present invention relates to an ultrasonic measurement apparatus and to the use of an apparatus or a system of this kind.
2. Description of the Prior Art
In the modern minimally invasive examination and treatment methods, image formation by means of ultrasound is accorded a special importance, among other things because it does without ionizing radiation, such as e.g. X-rays, and is thus not stressing for the patient or the doctor.
One of the numerous uses of image formation by means of ultrasound is, for example, trans-esophagal heart imaging, which is principally used for diagnostic purposes. Many of the usual ultrasonic systems today, however, produce only two dimensional images, and it is often very difficult even for specialists to analyze the three dimensional anatomy using such two dimensional images. Therefore, great efforts are being made to represent the anatomy by means of three dimensional ultrasonic images.
Ultrasonic systems which produce three dimensional images (in the following also designated as 3D-ultrasonic systems) are also already known from the prior art. In a known 3D-ultrasonic system a probe with an ultrasonic transducer is used which is pivotal with respect to two axes. Through a pivoting of the transducer about these two axes, which is usually done in an electronically controlled manner, the anatomy to be imaged, e.g. a heart chamber, is first sampled region-wise and sequentially by means of ultrasound, and a three dimensional image is then reconstructed in a data processing system from the echo signals obtained in this manner.
A substantial disadvantage of this known 3D-ultrasonic system consists in that the required sampling times for a sufficient spatial resolution of the image are relatively long. Known three dimensional systems typically require several, for example at least five, seconds for the production of a single three dimensional image. For such use as, for example, the navigation or localization of instruments required within the body, e.g. heart catheters for the ablation of stimulus lines in the heart, such long times for the image production are unsatisfactory since they are opposed to the need for a rapid and precise localization of the momentary position of the instruments in the body.